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  <title>Character sets</title>

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</div><hr /><div id="mysqlinfo.concepts.charset" class="section">
  <h2 class="title">Character sets</h2>

  <p class="para">
   Ideally a proper character set will be set at the server level, and doing this is described
   within the <a href="http://dev.mysql.com/doc/mysql/en/charset-configuration.html" class="link external">&raquo;&nbsp;Character Set Configuration</a>
   section of the MySQL Server manual. Alternatively, each MySQL API offers a method to set 
   the character set at runtime.
  </p>

  <div class="caution"><strong class="caution">Caution</strong>
   <h1 class="title">The character set and character escaping</h1>
   <p class="para">
    The character set should be understood and defined, as it has an affect on every
    action, and includes security implications. For example, the escaping mechanism
    (e.g., <span class="function"><a href="mysqli.real-escape-string.html" class="function">mysqli_real_escape_string()</a></span> for mysqli, <span class="function"><a href="function.mysql-real-escape-string.html" class="function">mysql_real_escape_string()</a></span>
    for mysql, and <span class="methodname"><a href="pdo.quote.html" class="methodname">PDO::quote()</a></span> for PDO_MySQL) will adhere to
    this setting. It is important to realize that these functions will not use the character
    set that is defined with a query, so for example the following will not have an effect
    on them:
   </p>
  </div>

  <div class="example" id="example-1528">
   <p><strong>Example #1 Problems with setting the character set with SQL</strong></p>
   <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /><br />$mysqli&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">mysqli</span><span style="color: #007700">(</span><span style="color: #DD0000">"localhost"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"my_user"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"my_password"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"world"</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">//&nbsp;Will&nbsp;not&nbsp;affect&nbsp;$mysqli-&gt;real_escape_string();<br /></span><span style="color: #0000BB">$mysqli</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">query</span><span style="color: #007700">(</span><span style="color: #DD0000">"SET&nbsp;NAMES&nbsp;utf8"</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">//&nbsp;Will&nbsp;not&nbsp;affect&nbsp;$mysqli-&gt;real_escape_string();<br /></span><span style="color: #0000BB">$mysqli</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">query</span><span style="color: #007700">(</span><span style="color: #DD0000">"SET&nbsp;CHARACTER&nbsp;SET&nbsp;utf8"</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">//&nbsp;But,&nbsp;this&nbsp;will&nbsp;affect&nbsp;$mysqli-&gt;real_escape_string();<br /></span><span style="color: #0000BB">$mysqli</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">set_charset</span><span style="color: #007700">(</span><span style="color: #DD0000">'utf8'</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
   </div>

  </div>

  <p class="para">
   Below are examples that demonstrate how to properly alter the character set at runtime
   using each each API.
  </p>

  <div class="example" id="example-1529">
   <p><strong>Example #2 Setting the character set example: mysqli</strong></p>
   <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /><br />$mysqli&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">mysqli</span><span style="color: #007700">(</span><span style="color: #DD0000">"localhost"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"my_user"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"my_password"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"world"</span><span style="color: #007700">);<br /><br />if&nbsp;(!</span><span style="color: #0000BB">$mysqli</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">set_charset</span><span style="color: #007700">(</span><span style="color: #DD0000">'utf8'</span><span style="color: #007700">))&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Error&nbsp;loading&nbsp;character&nbsp;set&nbsp;utf8:&nbsp;%s\n"</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$mysqli</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">error</span><span style="color: #007700">);<br />}&nbsp;else&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Current&nbsp;character&nbsp;set:&nbsp;%s\n"</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$mysqli</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">character_set_name</span><span style="color: #007700">());<br />}<br /><br /></span><span style="color: #0000BB">print_r</span><span style="color: #007700">(&nbsp;</span><span style="color: #0000BB">$mysqli</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">get_charset</span><span style="color: #007700">()&nbsp;);<br /><br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
   </div>

  </div>

  <div class="example" id="example-1530">
   <p><strong>Example #3 Setting the character set example: <a href="ref.pdo-mysql.connection.html" class="link">pdo_mysql</a></strong></p>
   <div class="example-contents"><p>
    Note: This only works as of PHP 5.3.6.
   </p></div>
   <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$pdo&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">PDO</span><span style="color: #007700">(</span><span style="color: #DD0000">"mysql:host=localhost;dbname=world;charset=utf8"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'my_user'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'my_pass'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
   </div>

  </div>

  <div class="example" id="example-1531">
   <p><strong>Example #4 Setting the character set example: mysql</strong></p>
   <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /><br />$conn&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">mysql_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">"localhost"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"my_user"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"my_pass"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$db&nbsp;&nbsp;&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">mysql_select_db</span><span style="color: #007700">(</span><span style="color: #DD0000">"world"</span><span style="color: #007700">);<br /><br />if&nbsp;(!</span><span style="color: #0000BB">mysql_set_charset</span><span style="color: #007700">(</span><span style="color: #DD0000">'utf8'</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$conn</span><span style="color: #007700">))&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">"Error:&nbsp;Unable&nbsp;to&nbsp;set&nbsp;the&nbsp;character&nbsp;set.\n"</span><span style="color: #007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;exit;<br />}<br /><br />echo&nbsp;</span><span style="color: #DD0000">'Your&nbsp;current&nbsp;character&nbsp;set&nbsp;is:&nbsp;'&nbsp;</span><span style="color: #007700">.&nbsp;&nbsp;</span><span style="color: #0000BB">mysql_client_encoding</span><span style="color: #007700">(</span><span style="color: #0000BB">$conn</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
   </div>

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